When I was a very heavy opioid user i didn't like them at all. Had to use a ton and it made me edgy like hydrocodone (no surprise here as hydrocodone's active metabolite is hydromorphone). I remember injecting a few 8mg tablets and felt like it was a huge waste of money. I'm sure I'd enjoy it now. Still, its not nearly as relaxing and full-bodied as heroin. I had a hard time sleeping on it as it was pretty stimulating and again, edgy. I'd be haply to have some in front of me now though (though I definitely wouldn't shoot it). Yet i actually probably would shoot it if I somehow came across a vial of hydromorphone formulated for parenteral use. Haven't injected anything in 10 years with the rule being that I can't inject anything that doesn't come in a non-expired, non-veterinary vial /ampules. But a vial of dilaudid hp would be an exception i suppose.